#include <stdio.h>
#include <string.h>
#include <stdbool.h>

#define Max(a,b) (((a)>(b)?(a):(b)))

int maxVowels(char* s, int k) {
    int max=0,current=0;
    bool checkTable[128]={ [0 ... 127]=false};
    checkTable['a']=checkTable['e']=checkTable['i']=checkTable['o']=checkTable['u']=true;
    for( int i=0; i<k; i++ ){
        if( checkTable[s[i]] ){
            current++;
        }
    }
    max=current;
    int len=strlen(s);
    for( int j=k; j<len; j++ ){
        if( checkTable[ s[j-k] ] ) 
            current--;
        if( checkTable[ s[j] ] )
            current++;
        max=Max(max,current);
    }
    return max;
}

int main(){
    char s[]="tryhard";
    printf("%d\n",maxVowels(s,4));
    return 0;
}
